Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T17/00—Component parts, details, or accessories of power brake systems not covered by groups B60T8/00, B60T13/00 or B60T15/00, or presenting other characteristic features
  • B60T17/18—Safety devices; Monitoring
  • B60T17/22—Devices for monitoring or checking brake systems; Signal devices
  • B60T17/221—Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
  • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
  • B60T13/66—Electrical control in fluid-pressure brake systems
  • B60T13/68—Electrical control in fluid-pressure brake systems by electrically-controlled valves
  • B60T13/683—Electrical control in fluid-pressure brake systems by electrically-controlled valves in pneumatic systems or parts thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
  • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
  • B60T13/24—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being gaseous
  • B60T13/26—Compressed-air systems
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
  • B60T8/32—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration
  • B60T8/321—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force responsive to a speed condition, e.g. acceleration or deceleration deceleration
  • B60T8/3255—Systems in which the braking action is dependent on brake pedal data
  • B60T8/327—Pneumatic systems

Definitions

• the present invention relates to a brake pressure modulator according to the preamble part of claim 1 for a pneumatic brake system and/or for a vehicle.
• the invention also relates to a respective pneumatic brake system and/or a vehicle.
• Such kind of brake pressure modulator comprises a relay valve for controlling a supply of pressurized air from a primary source to at least one brake actuator; a first valve sub-unit configured to be electronically actuated, wherein the first valve sub-unit is configured to receive a primary control pressure from the primary source intended for opening the relay valve; and a second valve unit configured to at least receive a secondary control pressure from a secondary source and at least part of the primary control pressure from the primary source and to transmit either the primary control pressure or the secondary control pressure to the relay valve, wherein when the secondary control pressure is transmitted to the relay valve, the primary control pressure from the primary source is disconnected, and/or when the primary control pressure is transmitted to the relay valve, the secondary control pressure from the secondary source is disconnected.
• the present invention relates to the brake pressure modulator operable by a pneumatic force that operates as, for example, a multi-relay valve for wheel end actuators associated with a pneumatic brake system.
• the brake pressure modulator of the present invention can be a pneumatic brake pressure modulator (PCV unit section, pressure control valve unit section) that is provided at either a front and/or auxiliary axle of the vehicle (AVP, axle valve package) or associated with applying control pressure for the trailer brake system.
• PCV unit section pneumatic brake pressure modulator
• AVP axle valve package
• Electronic brake systems allow precisely controllable and rapid braking of a vehicle.
• the output signal of a brake signal transmitter which depends on a deceleration demand of the driver, is passed to a control unit.
• the output signal of the brake signal transmitter can be modified additionally by driving safety systems, such as an antilock system, a traction control system or a system for electronic stability control.
• the control unit produces control signals, which are passed to "brake pressure modulators", which control the supply of a pressure medium, generally compressed air in the case of utility vehicles, to the individual braking devices or brake cylinders in a manner specific to the wheel or axle-wise by means of electro- magnetically actuable valve arrangements.
• the electronic brake system In the event that said control unit fails, e.g. because the power supply thereof is interrupted, the electronic brake system generally has a redundant device associated with the service brake or the pressure control system in order to be able to bring the vehicle safely to a halt, even in this operating situation, by brake actuation. More particularly, the redundant device comprises a modulator (PCV, pressure control valve) operable merely by a pneumatic force; this is without the need and/or independent of an electronic control.
• PCV pressure control valve
• Brake pressure modulators for controlling the pressurized airflow to the brake actuators associated with either a front axle or to the brake actuators associated with the trailer have been known in the art.
• US patent publication US 2017/210365 further discloses a conventional brake pressure modulator provided for the purpose of the controlling the flow of the pressurized flowed to the brake actuators.
• This conventional brake pressure modulators discloses use of a number of 2/2 solenoid control valves to manage the supply of the pressurized air from a brake signal transmitter to open or close one or more relay valves.
• FIG. 4 of the present application One such conventional brake pressure modulator 400 is also shown in FIG. 4 of the present application. This figure has also been clearly demarcated as ‘prior art’ in the drawings accompanying the present application. While the general functioning of brake pressure modulator 400 will be derivable to the person skilled in the art of the vehicle brake systems and from the above cited US patent publication US 2017/210365, it is nevertheless shortly (to the extent necessary) explained herewith.
• a relay valve 402 in order for service brake pressure inlet 410 to be connected with service brake pressure outlet 412 for pressure from reservoir II, a relay valve 402 should to be activated.
• a pneumatic pressure is applied for actuating relay valve 402 in order to selectively enable or disable such a connection between inlet 410 and outlet 412.
• This control pressure is derived from control pressure inlet 408 receiving pressurized fluid from a reservoir via brake signal transmitter (BST).
• BST brake signal transmitter
• the activation of relay valve 402 is however dependent on receiving the control pressure supply from e.g., a first valve unit 404 and/or a second valve unit 406. Based on the activation states of first and second valve units 404 and 406, the pressurized air is supplied to relay valve 402.
• first and second valve units 404 and 406 there are also default positions for first and second valve units 404 and 406 in which the pressurized air is supplied to relay valve 402 almost one of the two valve units 404 and 406 as safety precaution.
• the electronic control of valve units 404 and 406 not work, they retain default positions, which will still enable the pressurized air supply for actuating relay valve 402.
• the default positions of each of 2/2 solenoid valves provided in first and second valve units 404 and 406 will guarantee that the required connection between inlet 410 an outlet 412 is established so that during emergency brake application scenarios, when the driver presses the brake pedal (not shown in FIG. 4), the control pressure is still supplied to relay valve 402 to be activated.
• Such solutions may be referred to as safety braking solutions and may for instance be sometimes stipulated by regulations.
• UN-ECE Reg. No. 13, in the paragraph 5.2.1.18.3. provides one such requirement for trailer brakes in the situations, for instance, when an electric line is found to be defective.
• valve units 404 and 406 however can only be electronically actuated. Therefore, if valve units 404 and 406 require changing of positions from a ‘default’ position, solenoids of the respective valve units are indispensable. Furthermore, this requires additional wiring and related provisions within conventional brake pressure modulator 400. Needless to say, this has direct effect on the cost of the product due to additional manufacturing and constructional costs that using electronically controlled solenoids entail, but at the same time complying with the safety requirements of the regulations.
• FIG. 5 shows a cross-sectional view of the conventional brake pressure modulator 400 where the location of valves 406c, 404a and 404b is shown with valve units 404 and 406 as described before. Furthermore, inlets 408, 410, of modulator can also be located. However, what is most important is location of valve 406c. Valve 406c hereinafter is also referred to as an electronically actuable pressure control valve.
• valves 404a, 404b and 406c are placed in parallel positions within a modulator housing 502 of brake pressure modulator 400. As mentioned above, providing spatial allocation for three valves 404a, 404b and 406c arranged in parallel to each other and each of them being solenoid actuated may not be cost-effective.
• the major object of the invention is to provide a preferred brake pressure modulator wherein said mechanically operable valve is established and integrated in the brake pressure modulator in an advantageous way observing the above conditions.
• a brake pressure modulator comprising a relay valve for controlling a supply of pressurized air from a primary source (II) to at least one brake actuator,
• first valve sub-unit configured to be electronically actuated, wherein the first valve sub-unit is configured to receive a primary supply pressure form the primary source (II) as well as a connection to the ambient air for exhaust purposes, intended for controlling the relay valve, and
• a second valve unit configured to at least receive a secondary control pressure from a secondary source (‘BST’) and at least part of the primary control pressure from the primary source (II) and to transmit either the primary control pressure or the secondary control pressure to the relay valve, and wherein,
• the second valve unit is a mechanically operable valve in form of a pneumatically controlled valve having a valve casing, the valve casing comprising: - a pressurized guiding sleeve providing a valve chamber configured to axially guide a pressure pickup piston or the like spool adapted for pneumatic actuation thereof, in particular adapted for mere pneumatic actuation thereof, and
• a coil casing configured to provide a coil chamber peripheral next to the pressurized guiding sleeve, wherein the valve chamber is free of a spring and the coil chamber is free of a coil or the like solenoid, such that the spool is actuable pneumatically only, in particular wherein the spool is subject to a pneumatic force only due to pneumatic pressure in the valve chamber.
• the pneumatically controlled valve uses the same components of the existing solenoid valve, but without the spring and electrical coil that is used to excite the spool and/or assist in retaining said spool in the excited position.
• One of the technical advantages of providing the mechanically operable valve for the second valve unit is, unlike the second valve unit of conventional brake modulators with electronically controlled solenoid valve, space for wirings and other hardware requirements associated with the solenoid valve are done away with. This has a direct effect on the cost of the product as well as makes the brake pressure modulator more self- reliant and not always dependent on electronic control. In this certain way, the redundant functioning (or functioning of the brake modulator without electronic control) is boosted at the same time satisfying the safety requirements of the pneumatic braking system.
• the pneumatically controlled valve enables a simple mechanism in which selective transmission of the brake pressure is taken care of as only one of pressure lines can be connected to the relay valve for its actuation and as a result, same control achieved due to the usage of solenoid valves is achieved using the pneumatically controlled valve
• the pneumatically controlled valve can be established as an “only” mechanically operable valve, this is more precisely “only” a mechanically-pneumatically operable valve.
• the mechanically-pneumatically operable valve can be established generally in any form advantageous way to be integrated in the brake pressure and configured to switch between a first and a second state when receiving a first and/or second switch-control pressure derived from the primary and/or secondary control pressure.
• the invention also leads to a pneumatic brake system of claim19 and a vehicle of claim 20 comprising the pneumatic brake system.
• the pneumatic brake system comprises: the brake pressure modulator according to the invention or a development thereof; a centralized pressure modulator connected to the brake pressure modulator, and a centralized electronic control unit mounted on the central axle control valve wherein the centralized electronic control unit transmits control signals to at least the first valve sub-unit.
• valve chamber provides a spool chamber and a spring chamber, wherein the valve chamber provides an empty and/or hollow spring chamber, in particular wherein a spring space of the valve chamber is free of a spring.
• the coil chamber is empty and/or hollow, in particular wherein the coil chamber provides a coil space, which is free of a coil or the like solenoid.
• the pneumatically controlled valve is configured to switch between a first and a second state
• the pressurized guiding sleeve is configured to guide the pressure pickup piston or the like spool in a first position corresponding to the first state and in a second position corresponding to the second state, in particular wherein the first and second position of the spool are selected from positions on the valve seat and the spool stop respectively.
• valve chamber extends between a valve seat on a valve body and a spool stop on a first pressure-guiding casing path.
• a first pressure-guiding casing path provides a first pressurized path and a pressure pickup path
• valve body is resided in a second pressure-guiding casing part providing a second pressurized path.
• the spool includes a rubber base at at least one side of the spool, and/or
• valve body features a sealing ring.
• the pneumatically controlled valve is a double check valve, in particular wherein the double check valve is configured to switch between a first and a second state when receiving the primary and/or secondary control pressure.
• the double sided check valve is configured to selectively transmit the pressure of a higher magnitude among the primary and secondary control pressures received from the primary source (II) and the secondary source (BST), respectively.
• the second valve unit is a pneumatically controlled 3/2-directional valve that is configured to switch between a first and a second state when receiving a first and/or second switch-control pressure derived from the primary and/or secondary control pressure.
• the pneumatically controlled valve in particular a 3/2-directional valve, is configured to switch from the second to the first state when receiving the first switch-control pressure derived from the primary control pressure such that the primary control pressure is transmitted to the relay valve.
• the pneumatically controlled valve in particular a 3/2-directional valve, is configured to switch from the second to the first state when receiving the first switch-control pressure derived from the primary control pressure such that the primary control pressure is transmitted to the relay valve.
• the pneumatically controlled 3/2-directional valve in the second state is adapted to transmit the secondary control pressure to the relay valve and in the first state is adapted to transmit the primary control pressure to the relay valve.
• the pneumatically controlled valve in particular a double check valve or a 3/2-directional valve, is configured to switch from the second to the first state when receiving the first switch-control pressure derived from the primary control pressure such that the primary control pressure is transmitted to the relay valve.
• the pneumatically controlled 3/2-directional valve here is according to the above-mentioned first variant and switches a control pressure against a switch-control pressure.
• the variants of a double check valve and a 3/2- directional valve can be combined, in particular preferably with omitting the need for a valve spring.
• the pneumatically controlled valve in particular a double check valve or a 3/2-directional valve, is configured so as to selectively transmit the pressure of a higher magnitude among the primary and secondary control pressures received from the primary source (II) and the secondary source (BST), respectively.
• the pneumatically controlled valve here is according to the above-mentioned second variant and switches upon load by a first and a second switch-control pressure against each other.
• a respective piston loaded by a first switch-control pressure against a load of a second switch-control pressure of the piston is provided in the pneumatically controlled valve.
• the pneumatically controlled valve in particular a double check valve or a 3/2-directional valve, includes a spool with two opposing sides, wherein a first one among the two opposite sides receives the pressurized air from the primary source (II) and a second one among the two opposite sides receives the pressurized air from the secondary source (BST).
• the resulting configuration as provided in this development enables a mechanism that can translate the selective application through simple hardware means i.e., the spool configuration.
• the linear translation of the spool enables which supply of the pressurized air i.e., whether from the secondary source or from the primary source be given priority, based on the respective magnitude of the pressure.
• the pneumatically controlled valve in particular a double check valve or a 3/2-directional valve, includes a casing which covers the spool, wherein the spool is configured to linearly translate within the casing, and wherein the direction of movement of the spool within the casing is directly dependent on a difference in the magnitude of the pressure received from primary source (II) and the secondary source (BST).
• II primary source
• BST secondary source
• the first valve sub-unit which includes two solenoid controlled 2/2 direction control valves and wherein, based on an actuation state of each of the two direction control valves, the brake pressure modulator is configured to perform one of the following functions: - enabling the supply of the primary control pressure from the primary source (II) to actuate the relay valve;
• the relay valve, the first valve sub-unit, and the second valve unit are encompassed within a single cast body of the brake pressure modulator.
• all the components are incorporated in a single cast unit.
• aluminum or cast iron could be used make the cast body of the brake pressure modulator.
• the brake pressure modulator of any one of the above developments wherein the brake pressure modulator is for controlling supply of the pressurized air to the brake actuators associated with a front axle of a vehicle.
• a pneumatic brake system which system comprises the brake pressure modulator one or more of the above discussed developments, a centralized pressure modulator connected to the brake pressure modulator, and a centralized electronic control unit mounted on the central axle control valve wherein the centralized electronic control unit transmits control signals to at least the first valve subunit.
• a vehicle comprising the pneumatic brake system is disclosed.
• FIG. 1 illustrates a pneumatic brake system of a vehicle in accordance with an embodiment of the present invention
• FIG. 2 illustrates a brake pressure modulator with the mechanically operable valve in form of a pneumatically controlled double check valve in accordance with a prime preferred embodiment of the present invention
• FIG. 2a illustrates a brake pressure modulator with the mechanically operable valve in form of a pneumatically controlled 3/2-directional valve in accordance with a first preferred embodiment of the present invention
• FIG. 2b illustrates a brake pressure modulator with the mechanically operable valve in form of a pneumatically controlled 3/2-directional valve in accordance with a second preferred embodiment of the present invention
• FIG. 2c illustrates a brake pressure modulator with the mechanically operable valve in form of a pneumatically controlled 3/2-directional valve in accordance with a third preferred embodiment of the present invention
• FIG. 3a illustrates a mechanically operable valve (pressure control valve, PCV, in particular axle PCV (APCV)) in form of a pneumatically controlled valve of the brake pressure modulator as a PCV-unit-section for an axle valve package (AVP),
• PCV pressure control valve
• APCV axle PCV
• FIG. 3b the brake pressure modulator with a PCV unit section, wherein the axle PCV (APCV) as a preferred embodiment is shown in a cross-sectional view;
• APCV axle PCV
• FIG. 3c the brake pressure modulator of FIG. 3a view (A) with the pressure control valve PCV in assembled form;
• FIG. 3d the brake pressure modulator as a PCV-unit-section with a PCV, respectively a APCV (axle pressure control valve), in a perspective partly cut out view to the APCV (axle pressure control valve) which is used instead of an electronically actuable valve;
• APCV axle pressure control valve
• FIG. 3e the brake pressure modulator in assembled form with the PCV of FIG. 3b;
• FIG. 4 illustrates a conventional brake pressure modulator of prior art with electronically actuable valves
• FIG. 5 illustrates a cross-sectional view of the conventional brake pressure modulator of Fig. 4.
• FIG. 1 illustrates a pneumatic brake system 100 of a vehicle (not labeled) in accordance with an embodiment of the present invention.
• the vehicle includes pneumatic brake system 100.
• Pneumatic brake system 100 in general includes a centralized (brake) pressure modulator 102, which is configured, inter alia, to receive a brake control input in the form of control pressure from a brake signal transmitter (labeled as ‘BST in FIG. 1) and in a preferred embodiment, to receive electronic signals from Electronic Stability Controller Module (ESCM) 102a connected to it via e.g. CAN (Controller Area Network) bus.
• centralized pressure modulator 102 is also connected to a Power Line Carrier (PLC) 108 that is connected, for example, to a trailer (not shown in figure 1). It is noted that the driver of the vehicle actuates a brake pedal or BST to supply brake pressure to wheel end actuators 112a, 112b, 112c, 112d associated with different wheels (not shown in the figure).
• PLC Power Line Carrier
• the BST simply transmits an electronic signal using a stroke sensor (not shown in FIG. 1) to read a control output from a brake pedal (not shown in FIG. 1) to a central brake pressure modulator unit provided in combination with centralized pressure modulator 102.
• Said stroke sensor (not shown in FIG. 1 ) is configured to read or determine the movement of a plunger as a result of the driver applying pressure on the brake pedal.
• centralized pressure modulator 102 On receiving the control inputs from the BST, centralized pressure modulator 102 transmits control pressure to the brake pressure modulators, in particular to the ones located at front axle ‘FA’ as well as to the brake pressure modulator assigned for trailer brakes.
• the brake pressure modulator assigned for the front axle brakes is labeled as “110”
• the brake pressure modulator assigned for the trailer brakes is labeled as “106”.
• the control pressure is transferred to respective wheel end actuators 112a, 112b, 112c and 112d through which the vehicle brakes are applied.
• accumulators or reservoirs displayed in FIG. 1 are for supplying pressurized air to different receivers present within pneumatic brake system 100.
• reservoir T is configured to supply pressurized air to wheel end actuators 112c and 112d present at the rear axle of the vehicle whereas reservoir ‘III’ is predominantly for applying parking brakes and supplying pressurized air to trailer brake pressure modulator 106.
• Reservoir ‘II’ is for supplying pressurized air to front axle brake control modulator 110.
• Pneumatic brake system 100 of the present embodiment also additionally discloses wheel speed sensors WSS1 , WSS2, WSS3 and WSS4 located at each of the wheels to determine their rotational speeds, a CAN network unit 114 (refers to a networking unit operating via CAN protocol), an on-board battery 116, and a steering angle sensor 118.
• CAN network unit 114 refers to a networking unit operating via CAN protocol
• an on-board battery 116 refers to a steering angle sensor 118.
• pneumatic brake system 100 includes also park brake control unit denoted as -PB - in FIG. 1.
• PB is connected to brake pressure modulator 104, which in accordance with an embodiment used for modulating parking brakes, and which is also associated with the spring brakes (or e.g., the actuators 112c and 112d) of a rear axle, (denoted as -‘RA’ - in FIG. 1).
• brake pressure modulators 110 and/or 106 of the present invention are provided in the forthcoming sections. To the extent the subject-matter of the present invention relates to the brake pressure modulator 110 associated with front axle FA of the vehicle, the underlying features of the claimed invention and the technical teaching associated with the brake pressure modulators provided at other parts of pneumatic brake system 100, including centralized pressure modulator 102, trailer brake pressure modulator 106 and exceptionally, rear axle pressure modulator or relay valve 106.
• FIG. 2, FIG. 2a, FIG. 2b and FIG. 2c each respectively in a scheme of circuit diagram illustrate a brake pressure modulator 110, 110a, 100b, 100c in accordance with an embodiment of the present invention, which each can be provided as a brake pressure modulator 110, 106 -in particular the front axle brake control modulator 110 and/or a trailer brakes pressure modulator 106- shown in FIG. 1.
• the brake pressure modulator 110, 110a, 100b, 110c comprises a relay valve 202 for controlling a supply of pressurized air from a primary source (II) to at least one brake actuator of 112a, 112b (see FIG. 1).
• relay valve 202 actuation of relay valve 202 enables connection between supply lines 202.1 and 202.2.
• Supply line 202. 1 is connected to reservoir ‘II’ (see FIG. 1 ) whereas supply line 202.2 leads to Anti-lock Braking System valves ABS-1 and ABS-2 (see FIG. 1) and consequently, to wheel end actuators 112a and 112b.
• relay valve 202 In order to open and/or close relay valve 202, typically, a control pressure is required.
• the second valve unit 206 in accordance with the present embodiments of FIG. 2, FIG. 2a, FIG. 2b and FIG. 2c, is a mechanically operable valve in form of a pneumatically controlled valve, also referred to with reference mark 206 for the second valve unit.
• control input line 206.1 for instance, is connected to a first valve sub-unit 204 whereas control input line 206.2 is connected to BST (see FIG. 1).
• the second valve unit 206 is a mechanically operable valve, which will now be described below with regard to FIG. 2 in detail as a functioning like a pneumatically controlled double check valve 206D of the second valve unit 206.
• the description also holds for FIG. 2a, FIG. 2b and FIG. 2c in principle; details and differences follow with explicit reference to FIG. 2a, FIG. 2b and FIG. 2c.
• first valve sub-unit 204 is configured to be electronically actuated, wherein first valve subunit 204 is configured to receive a primary control pressure Pel from the primary source such as reservoir ‘II’ intended for opening relay valve 202.
• a primary control pressure Pel from the primary source such as reservoir ‘II’ intended for opening relay valve 202.
• the second valve unit 206 is a mechanically operable valve. It is configured to at least receive a secondary control pressure Pc2 from a secondary source (such as ‘BST of FIG.
• the relay valve 202 to e.g., open, and wherein, when the secondary control pressure is transmitted to the relay valve 202, the primary control pressure from the primary source (such as reservoir ‘II’ of FIG. 1 ) is disconnected and/or when the primary control pressure is transmitted to the relay valve 202, the secondary control pressure from the secondary source (BST) is disconnected.
• the second valve unit 206 receives at least part of the primary control pressure Pel from the primary source via the first valve sub-unit 204.
• the first valve sub-unit 204 includes two solenoid controlled 2/2 direction control valves 208, 210 and wherein, based on an actuation state of each of the two direction control valves 208 and 210, brake pressure modulator 1 10a is configured to perform one of the following functions:
• FIG. 2 provides a mechanically operable valve, which is functioning like and -in this embodiment- is formed as a pneumatically controlled double check valve 206D; the structure is advantageously integrated in the brake pressure modulator as will be further elucidated with regard to FIG. 3a to FIG. 3e.
• the mechanically operable valve is a pneumatically controlled 3/2-directional valve that is configured to switch between a first and a second state when receiving a first and/or second switch-control pressure P1 , P2 derived from the above mentioned primary and/or secondary control pressure Pel , Pc2; at least the embodiment of FIG. 2c is operated in a preferred nearest analogy to the prime preferred embodiment of a pneumatically controlled double check valve 206D in FIG. 2.
• FIG. 2a, FIG. 2b and FIG. 2c respectively each embodiment features a pneumatically controlled 3/2-directional valve 206A, 206B, 206C and in the second state (shown in the figures FIG. 2a, FIG. 2b and FIG. 2c) it is adapted to transmit the secondary control pressure Pc2 to the relay valve 202 and in the first state it is adapted to transmit the primary control pressure Pel to the relay valve 202.
• These two states have been shown to be particular advantageous to be established in the pneumatically controlled 3-port/2-way-directional valve 206A, 206B, 206C.
• the pneumatically controlled 3/2-directional valve 206A, 206B, 206C is established as an “only” mechanically operable valve; this is more precisely “only” a mechanically-pneumatically operable valve. This means the mechanically-pneumatically operable valve switches without electrical or electro-magnetic aid.
• the mechanically-pneumatically operable valve is established in form of the pneumatically controlled 3/2-directional valve 206A, 206B, 206C configured to switch between a first and a second state when receiving a first and/or second switch-control pressure P1 , P2 derived from the primary and/or secondary control pressure and/or above mentioned primary and/or secondary control pressure Pel , Pc2 - the choice of control is different in each of the embodiments shown in FIG.2a, Fl.2b, FIG.2c.
• Pc2 the choice of control is different in each of the embodiments shown in FIG.2a, Fl.2b, FIG.2c.
• at least the embodiment of the pneumatically controlled 3/2-directional valve 206C of FIG. 2c is operated in nearest analogy to the prime embodiment of a pneumatically controlled double check valve 206D.
• the “only” mechanically operable valve replaces an electro-magnetic actuable pneumatic valve of the valve unit with electronically actuate valve 406 shown in FIG. 4 and
• the mechanically operable valve -in particular the double check valve 206D in FIG. 2 or the pneumatically controlled 3/2-directional valve 206A, 206B, 206C- is advanta- geously integrated in the brake pressure modulator 110, 106 as will be further elucidated with regard to FIG. 3a to FIG. 3e.
• the mechanically-pneumatically operable valve in form of the pneumatically controlled 3/2-directional valve 206A, 206B switches when receiving a first and/or second switch-control pressure P1 , P2 against a primary and/or secondary control pressure Pel , Pc2.
• the pneumatically controlled 3/2-directional valve 206A is configured to switch from the second state “2” to the first state “1” when receiving the first switch-control pressure P1 in switch-control line 206.4 derived from the primary control pressure Pel such that the primary control pressure Pel from control input line 206.1 is transmitted to the relay valve 202 via control output line 206.3.
• the pneumatically controlled 3/2-directional valve here is according to the above-mentioned first variant and switches against a secondary control pressure Pc2.
• a respective piston 206.6 loaded by a first switch-control pressure P1 against a secondary control pressure Pc2 load of the piston 206.6 is provided in the pneumatically controlled 3/2-directional valve.
• the piston is pressure loaded with first switch-control pressure P1 via a respective pressure port 206.7.
• the pneumatically controlled 3/2- directional valve 206B is configured to switch from the first state “1” to the second state “2” when receiving the second switch-control pressure P2 in switch-control line 206.4 derived from the secondary control pressure Pc2 such that the secondary control pressure Pc2 from control input line 206.2 is transmitted to the relay valve 202 via control output line 206.3.
• the pneumatically controlled 3/2-directional valve here is according to the above-mentioned first variant and switches against a primary control pressure Pel .
• a respective piston 206.6 loaded by second switch-control pressure P2 against a primary control pressure Pel load of the piston 206.6 is provided in the pneumatically controlled 3/2-directional valve.
• the piston is pressure loaded with second switch-control pressure P2 via a respective pressure port 206.7.
• it is configured to selectively transmit the pressure of a higher magnitude among the primary and secondary control pressures received from the primary source (II) and the secondary source (BST), respectively.
• the piston “206.6A to 206. B” is pressure loaded via respective pressure ports 206.7A and 206.7B with first and second switch-control pressure P1 , P2.
• the pneumatically controlled 3/2-directional valve 206C is configured so as to selectively transmit the pressure of a higher magnitude among the primary and secondary control pressures received from the primary source (II) and the secondary source (BST), respectively.
• the pneumatically controlled 3/2- directional valve here is according to the above-mentioned second variant and switches upon load by a first and a second switch-control pressure P1 , P2 against each other.
• a respective piston loaded by a first switch-control pressure against a load of a second switch-control pressure of the piston is provided in the pneumatically controlled 3/2-directional valve.
• the pneumatically controlled 3/2-directional valve 206A, 206B, 206C or a double check valve 206D includes a spool with two opposing sides, wherein a first one among the two opposite sides receives the pressurized air from the primary source (II) and a second one among the two opposite sides receives the pressurized air from the secondary source (BST).
• the resulting configuration as provided in this embodiment enables a mechanism that can translate the selective application through simple hardware means i.e., the spool configuration.
• the linear translation of the spool enables which supply of the pressurized air i.e., whether from the secondary source or from the primary source be given priority, based on the respective magnitude of the pressure.
• the pneumatically controlled 3/2-directional valve 206A, 206b, 206C or double check valve 206D includes a casing which covers the spool, wherein the spool is configured to linearly translate within the casing, and wherein the direction of movement of the spool within the casing is directly dependent on a difference in the magnitude of the pressure received from primary source (II) and the secondary source (BST).
• the mechanically operable spool valve enables the Boolean operation of supplying the connection with a higher pressure air supply.
• the surface interaction between the spool and the casing enables realizing the simple mechanism of three ports, to position configuration direction control valve with minimal number of components.
• first solenoid controlled 2/2 direction control valve 208 when first solenoid controlled 2/2 direction control valve 208 is in an open state, supply of at least part of the primary control pressure form the primary source such as reservoir II is allowed. When said valve 208 is in closed state, the supply of the primary control pressure from the primary source (II) to relay valve 202 is either disabled or blocked. In the same example, when valve 208 is in the open state, the primary control pressure exits valve 208 at port 208.2.
• valve 210 includes first and second connection ports 210.1 and 210.2 where first connection port 210 is configured to act as inlet port for valve 210 and second connection port 210.2 is configured to act as outlet port for valve 210.
• the second valve unit 206 is a pneumatically controlled 3/2-directional valve 206A, 206B, 206C or double check valve 206D that is configured to switch between a first and a second state when receiving a first and/or second switch-control pressure derived from the primary and/or secondary control pressure.
• the pneumatically controlled 3/2- directional valve 206A, 206B, 206C or double check valve 206D in the second state is adapted to transmit the secondary control pressure to the relay valve 202 and in the first state is adapted to transmit the primary control pressure to the relay valve 202.
• the pneumatically controlled 3/2-directional valve 206A is configured to switch from the second to the first state “1” to “2” when receiving the first switch-control pressure derived from the primary control pressure such that the primary control pressure is transmitted to the relay valve 202, and/or the pneumatically controlled 3/2-directional valve 206B is configured to switch from the first to the second state when receiving the second switch-control pressure derived from the secondary control pressure such that the secondary control pressure is transmitted to the relay valve 202.
• the pneumatically controlled 3/2-directional valve 206C is configured to selectively transmit the pressure of a higher magnitude among the primary and secondary control pressures received from the primary source (II) and the secondary source (BST), respectively.
• the primary technical advantage of the presence of the mechanically operable valve in form of the pneumatically controlled 3/2-directional valve 206A, 206B, 206C or double check valve 206D is to, for instance, prevent additional wiring elements and associated space constraints by simply providing a mechanical solution that is workable in all pressure differential conditions. For instance, a minor difference in pressure magnitude between the pressurized air received from e.g., ports 206.1 and 206.2 makes a spool to move. This opens the possibility of the pressure with higher magnitude to be supplied for actuating relay valve 202 and making it to open connection between lines 202.1 and 202.2. For a manufacturer, such as the Applicant, considering the number of products manufactured, this results in also considerable cost savings.
• brake pressure modulator 110c of the present embodiment of the pneumatically controlled 3/2-directional valve 206C or double check valve 206D includes the spool 320 , in particular, with two opposing sides, wherein a first one among the two opposite sides receives the pressurized air from the primary source (II) e.g., via port 206.1 and a second one among the two opposite sides receives the pressurized air from the secondary source (BST) e.g., via port 206.2.
• the pneumatically controlled 3/2-directional valve 206C or double check valve 206D includes a valve casing 304 which covers the spool 320, wherein the spool 320 is configured to linearly translate within the casing and wherein the direction of movement of the spool within the casing is directly depended on a difference in the magnitude of the pressure received from primary source (II) and the secondary source (BST). Further details on the type of functioning of the pneumatically controlled 3/2- directional valve 206C or double check valve 206D and its technical characteristics are explained in reference to figs. 3a to 3e below.
• a pressure sensor 212 is provided in supply pressure line 202.2 connecting relay valve 202 and port 202.5, which connects to actuators 112a and 112b. This pressure sensor 212 sends readings to centralized brake pressure modulator 102, for instance, to determine the presence of flow of pressurized air in line 202.2 and or the magnitude of the pressure.
• valves 208, 210 are electronically actuable based on the pressure modulating signals received from centralized pressure modulator 102.
• electronically controlled braking processes such as Electronic Braking System, anti-roll braking methods, anti-skid braking methods, anti-jackknifing methods are implemented through the controlled logic stored in centralized pressure modulator 102, which naturally may include an electronic processing unit of suitable caliber.
• the mechanical pneumatic pressure control valve is formed as a 3/2-switch valve 206A, 206B, 206C or a double check valve 206D as will be described further below, respectively and has been indicated in FIG. 2a, FIG. 2b, FIG. 2c already, namely as a 3/2-mechanical pneumatic switch valve 206A, 206B, 206C or a double check valve 206D with a pressure pickup piston or the like spool 320 as is shown in FIG. 3a, view (C).
• the pressure pickup casing part 304.3 for receiving the pickup pressure to the pressure pickup piston or the like spool, which is more generally the pressure pickup piston or the like spool 320 as shown in view (C) of FIG. 3a - the pressure pickup piston or the like spool 320 corresponds to piston 206.6, 206.6A, 206, 6B as outlined above.
• the pneumatically controlled valve 206D, 206A, 206B, 206C is configured to switch between a first and a second state
• the brake pressure modulator 110,106 thus has the pressurized guiding sleeve 304.4, which is configured to guide the pressure pickup piston or the like spool 320 in a first position corresponding to the first state and in a second position corresponding to the second state, in particular wherein the first and second position of the spool 320 are selected from positions on the valve seat 307 and the spool stop 308 respectively as shown in FIG. 3a view (C).
• FIG. 3a schematically shows an embodiment to illustrate the principle of the invention as compared to the embodiment of FIG. 3a view (C); the inventive principle can be drawn from a comparison of three views (A), (B) and (C) of FIG. 3a thereof.
• FIG. 1 a picture of a pressure control valve unit section (PCV-unit section) is shown; in the instant case, the PCV-unit section is provided as an axle valve package AVP.
• the PCV-unit section is shown with comprising an exhaust valve EV and a supply valve SV and position for a back-up valve BUV.
• the back-up valve BUV deliberately is missing therein in a free space, which has been chosen for illustrations reasons.
• a back-up valve BUV is provided as a pressure control valve PCV’ as commonly known and shown in view (B) of FIG. 3a or in the present case -according to an embodiment of the instant invention- as a pressure control valve PCV as shown in view (C) of FIG. 3a.
• a further control valve is shown as a magnetopneumatic valve.
• the pressure control valve is shown according to the concept of the invention as a mechanical pneumatic valve; namely as a mechanically and pneumatically controlled 3/2-directional valve 206A, 206B, 206C with a pressure pickup piston or the like spool 320 as described above.
• the PCV-Unit section is formed as an axle PCV valve unit section APCV and the backup valve BUV is formed as an axle valve of the axle valve package respectively - this is, the backup valve is formed as an axle valve whereas the pressure control valve unit section is formed as an axle valve package AVP.
• an axle valve package are also suitable to be applied to a trailer valve package TVP that follows the same principle corresponding to the following embodiments.
• the backup valve BUV as a pressure control valve, axle pressure control valve respectively (PCV).
• a usual pressure control valve PCV’ as for instance shown with Fig.4 as an electro pneumatic 2/2-valve, is shown.
• the pressure control valve PCV’ has a commonly known valve casing 304 with a first pressureguiding casing part 304.1 and a second pressure-guiding casing 304.2 and possibly an pressure pickup casing part 304.3 in case of the PCV according to the invention to the valve casing 304.
• the pressurized guiding sleeve 304.4 holds therein a valve body 310 with valve seat, a pressure pickup piston or the like spool 320 for interaction to close and open respectively the first and second pressurized path 331 , 332, in particular the respective first and second pressurized port 331 , 332 in the first and second pressure-guiding casing part 304.1 , 304.2 to selectively guide, pressurized air through the valve body 304.
• the pressure control valve PCV’ is in the form of a magneto-pneumatic switch valve, wherein the solenoid piston interacts upon force applied by a solenoid 311 to the pressure pickup piston or the like spool 320 against the force of a spring 321 provided in the above-mentioned first pressure-guiding casing part 304.1.
• the coil casing 304.5 of the valve casing 304 is shown to cover and hold the solenoid 311 .
• the gist of the invention starts from the fact that while a mechanical pneumatic pressure control valve PCV has advantages in operation, still nevertheless, packaging thereof in an axle or trailer valve package is also efficient for low weight and package volume of a pressure control valve PCV is to be reduced.
• the inventive pressure control valve PCV as shown in the preferred embodiments of FIG. 2a, FIG. 2b and FIG. 2c here in FIG. 3a view (C), for a PCV unit section as shown in view (A) of FIG.
• the pressure control valve according to the invention PCV is structured as a mechanical pneumatic pressure control valve without spring and without solenoid 321 , 311.
• the second valve unit 206 is a mechanically operable valve, in form of a pneumatically controlled valve 206D, 206A, 206B, 206C, and has a valve casing 304.
• the valve casing 304 comprises:
• a pressurized guiding sleeve 304.4 providing a valve chamber 305 configured to axially guide a pressure pickup piston or the like spool 320 adapted for pneumatic actuation thereof, in particular adapted for mere pneumatic actuation thereof, and
• a coil casing 304.5 configured to provide a coil chamber 306 peripheral next to the pressurized guiding sleeve 304.4.
• valve chamber 305 is free of a spring 321 and the coil chamber 306 is free of a coil or the like solenoid 311 , such that the spool 320 is actuable pneumatically only, in particular wherein the spool 320 is subject to a pneumatic force only due to pneumatic pressure in the valve chamber 305.
• FIG. 3b shows, in detail, an axle pressure control valve APCV as a particular embodiment of the pressure control valve PCV of the invention as shown in view (C) of FIG. 3a.
• the axle pressure control valve APCV is shown as part of an APCV valve unit section in a cross-sectional view with the APCV to form the backup valve, respectively the pressure control valve, a supply valve SV and an exhaust valve EV.
• the supply valve SV and the exhaust valve EV are generally of a known kind with pressure path connected in the APC valve unit section wherein the pressure path 330 is directed to the first pressure path 331 , in particular port, and a second pressure path 332, in particular port, as indicated above and further, the pressure pickup path 333, in particular port, as has been shown with view (C) of FIG. 3a.
• the APCV is well suitable to be assembled in the axle valve package as shown in FIG. 3b and FIG. 3c; this is more particularly, it has been shown that by forming the APCV as a pneumatically controlled 3/2-directional valve 206A, 206B, 206C or double check valve 206D -that is configured to switch between a first and a second state when receiving a first and/or second switch-control pressure Pel , Pc2 derived from the primary and/or secondary control pressure P1 , P2 as described above or directly the primary and/or secondary control pressure P1 , P2 as described above with a pressure pickup piston or the like spool 320- said APCV, according to the concept of the invention, can use the same package structure as a magneto-pneumatic APCV with a magneto-pneumatic pressure control valve PCV’ (as shown in view (B) of FIG. 3a).
• a magneto-pneumatic APCV with a magneto-pneumatic pressure control valve PCV’ (
• a mechanically operable valve for use as a pressure control valve PCV in principle can be construed in other form, still nevertheless, the form of the instantly invented 3/2-mechanical pneumatic switch valve with a pressure pickup piston or the like spool 320 is particularly useful, as the packaging structure as such is preserved, which has various advantages with consistency and conformity of existing products and assembly thereof.
• FIG. 3d shows the backup valve BUV, respectively pressure control valve PCV, namely, in particular in this case the axle pressure control valve APCV as part of the APCV valve unit section in a three-dimensional cutout sectional view, wherein the pressure ports 331 respectively 206.1 from pilot valves and 332, respectively 206.2 from control port BST are shown in addition to the control port 333 to connect to the relay control room in the main body sleeve of the pressure control valve PCV.
• valve chamber 305 provides a spool chamber 305V and a spring chamber 305S, wherein the valve chamber 305 provides an empty and/or hollow spring chamber 305S, in particular wherein a spring space 305SR of the valve chamber 305 is free of a spring 321 .
• the coil chamber 306 is empty and/or hollow, in particular wherein the coil chamber 306 provides a coil space 306C, which is free of a coil or the like solenoid 311 (thus indicated in fading dashed lines; which means that the coil space 306C has no solenoid 311).
• the valve chamber 305 extends between a valve seat 307 on a valve body 310 as described before and a spool stop 308 on a first pressure-guiding casing part 304.1.
• the brake pressure modulator 110,106 thus provides for a first pressure-guiding casing part 304.1 , which has a first pressurized path 331 and a pressure pickup path 333, and the valve body 310 is resided in a second pressure-guiding casing part 304.2 providing a second pressurized path 332.
• the spool 320 includes a rubber base at at least one side of the spool, and the valve body 310 features a sealing ring.
• FIG. 3e illustrates a cross-sectional view of brake pressure modulator 110 in accordance with an embodiment of the present invention.
• a brake pressure modulator 110 of the present invention is shown to include the pneumatically controlled 3/2-directional valve 206A, 206B, 206C or a double check valve 206D in exact the same position as electro- magnetic actuable valve 406 provided in conventional brake pressure modulator 400 of FIG. 5, without effecting further detailed changes within a housing 312 of brake pressure modulator 400.
• each of two solenoid controlled 2/2 direction control valves 208, 210 within brake pressure modulator 110 or 106 is same as the spatial requirement of double sided check valve 206.
• the (only) pneumatically controlled valve -this is a 3/2-directional valve 206A, 206B, 206C or a double sided check valve 206D as such as described above- of the present invention and also solenoid operated valve 406 of a conventional brake modulator 400, even though provided in exactly same spatial constraints, they act in a similar manner in allowing both pneumatic control from BST as well as electric control provided by first valve sub-unit 204.
• This results in a considerable cost saving and has an effect on the total pricing of brake pressure modulators such as ‘110’ or ‘106’. For a volume manufacturer, such as the applicant, this results in not only simply constructed brake pressure modulator, may also reduce the assembly costs.
• WSS1 , WSS2, WSS3, WSS4 Wheel speed sensors associated with respective wheels
• ABS1 ABS1 - Anti-lock Braking System
• the second valve unit a mechanically operable valve in form of a pneumatically controlled valve
• 206A, 206B, 206C pneumatically controlled valve as a 3/2-directional valve

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• Engineering & Computer Science (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Braking Systems And Boosters (AREA)
• Regulating Braking Force (AREA)
• Valves And Accessory Devices For Braking Systems (AREA)

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Publications (1)

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ID=72915822

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• 2020
  • 2020-10-14 EP EP20792966.2A patent/EP4228942A1/de active Pending
  • 2020-10-14 WO PCT/EP2020/078838 patent/WO2022078584A1/en unknown
  • 2020-10-14 US US18/031,655 patent/US20230391304A1/en active Pending
  • 2020-10-14 CN CN202080103857.XA patent/CN116157307A/zh active Pending

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